Pump mechanism



United States Patent 3,200,763 PUMP MECHANISM Holland S. Lippincott,Riverton, N.J., assiguor to Philco Corporation, Philadelphia, Pa., acorporation of Delaware Filled Dec. 21, 1962, Ser. No. 246,422 4 Claims.(Cl. 103231.5)

This invention relates generally to pump mechanisms and moreparticularly to a novel and improved means for effecting pressuredischarge of condensatefrom air-conditioning apparatus.

While of broader application the invention will be described inconnection with its use with dehumidifying equipment.

Dehumidifiers and other air conditioning apparatus which are currentlyavailable commonly rely on gravity discharge or On manual servicing forthe elimination of condensate generated during their operation. Whilepump mechanisms are available for use with systems not adapted forgravity discharge their use has proven commercially unacceptable becauseof the relatively high cost, noise, and complexities of installationattendant their use.

It is accordingly a general object of the instant invention to providenovel and improved pump mechanism for overcoming the limitations anddeficiencies of the prior art.

Another and more particularized object of the invention is the provisionof simple and inexpensive means for effecting automatic, pressuredischarge of condensate from air conditioning equipment.

These, and other objects and features of the present invention will beapparent from a consideration of the following detailed descriptiontaken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a partially cut away, sectionalized elevation of a preferredform of the invention; and

FIGURE 2 is a detailed sectional showing of one form of valveconstruction usable in apparatus of the type shown in FIGURE 1.

A preferred form of the invention is shown in FIG- URE l. The basiclements of which comprise a pump mechanism and liquid storage means 12,interconnected by valved conduit means 14 and 16.

The pump mechanism 10 comprises a closed container 18 from which anelectrically conductive liquid, in the illustrated case watercondensate, is expelled by vapor pressure generated by the establishmentof an electrically conductive path between electrode elements 28positioned within the container. Condensate is supplied to the container18 through valving 22 designed to prevent flow of liquid in a directionaway from the container while permitting its flow towards the container.The air-vent line 16 is also provided with a valve 24-, permittingescape of air displaced by the incoming liquid, which valve is furtherconstructed to close when the mass flow rate exceeds that resulting fromwater inflow, whether the media flowing out the valve is in the form ofgas, liquid or an admixture of both, and to open on equalization of thecontainers internal pressure with that of the ambient atmosphere.

An essential and characterizing element of the assembly is the provisionof a vessel in fluid flow communication with the container for housingthe condensate heating means. Advantageously, this vessel comprises acup, such as the cup shown at 25, disposed contiguous the bottom of thecontainer, into which terminal portions of the electrode elements 20extend. It is a function of the cup to insulate the electrodes fromliquid surrounding the cup within the container until the liquid risesto a height overflowing the cup. When overflow occurs, an electricallyconductive path is established between the 3,200,763 Patented Aug. 17,1965 electrodes, resulting in current flow and the generation of heateffective to bring about gradual vaporization of the contained liquid.The electrode system is preferably designed so that the resulting vaporpressure generated by its operation is not effective to shut off flow offluid into the container until the container is substantially full. Atthis point pressure within the system reaches a value effecting closureof the valves in both the liquid inlet line 14 and air-venting conduit16. The continued build up of pressure forces water out the non-valveddischarged line 23, the open end 30 of which is sealed by water withinthe container. As seen in FIGURE 1, the discharge line extends into thecontainer to a depth below the level of the top of the cup so that waterentering the container seals the discharge opening 30 before overflow ofwater into the cup initiates the heating phase of the cycle. To optimizethe quantity of water which the pump can handle per cycle of operationthe opening 30 of the discharge line is located as near the bottom ofcontainer 18 as is possible. To prevent blockage of opening 30 by thebottom of the container the opening is chamfered in the manner shown inFIGURE 1.

An essential requisite of operation is that the liquid being pumped beelectrically conductive. Experimentation has disclosed that condensateproduced as a result of dehumidifier operation is suflicientlyconductive to support the type of operation disclosed. It is believedthat the conductive properties of the condensate are primarily a resultof its exposure to metal surfaces within the system such, for example,as the evaporator coils of the air-conditioning apparatus over which thecondensate initially flows, the condensate pan, interconnecting tubingand other ionizing surfaces. It should be noted in this connection thatshould a particular installation require the condensate to be ionizedbecause of a lack of the above causes, this can be readily accomplishedfor example by disposing a suitable metallic element, such as amagnesium strip, within the line over which the condensate must flow tothe container, or alternatively by installing an ionizing element withinthe container proper. The electrodes themselves may be used for thispurpose. The first two suggested forms have not been shown in theillustrated drawings, since their installation is believed well withinthe skill of the average artisan. Any variance in electricalconductivity between liquids can be readily compensated for by modifyingthe shape of the electrode elements or by changing their spacing or by acombination of both approaches. The lower the electrical conductivity ofthe media being pumped the closer the spacing and the greater theelectrode area required.

Referring in greater detail to FIGURE 1, the pumping system shown is inits inoperative state, the ball check valves 22 and 24, disposedrespectively in lines 14 and 16, being shown in full lines in their restor unseatcd position.

When the liquid collecting in the condensate pan 12, such, for example,as the condensate produced during normal operation of a dehumidifier,reaches the level of the feed siphon discharge outlet 32 it spills overinto container 13. This initiates siphonic action between the condensatepan and container which continues to remove water from the pan 12 untileither the water level in the pan and container are equalized, or thefeed check valve 22 is close-d by back pressure developed within thecontainer by operation of the electrode system.

This latter action will be the assumed mode of operation in thedescription which follows. As the liquid, which in the illustrated caseis assumed to be water, enters the container 18, air within thecontainer displaced by water is discharged through the vent check valve24. The outflow of air resulting from the inflow of water, is notsufficient to seat the ball 34 and acpressure.

co-rdingly air is allowed to pass out of container 18. One form of valveconstruction designed to achieve this end is shown in FiGURE 2, theoperational details of which will be later described. In the embodimentshown, conduit 16 is placed in communication with the condensate pan 12in order to recapture any blow-through of water which might occur byreason of ball 34 not immediately seating on the unit coming up tooperating Disposed within the container 18 as previously mentioned is acup 26 preferably held captive therein by electrodes 20. In theembodiment shown the cup is free to float as the water fills thecontain-er insuring complete immersion of terminal portions of theelectrodes even during condition-s of partial fill in which the waterlevel rises to just slightlyabove the cup 'rim. To avoid shorting of theelectrode element 20 the cup is made of electrically insulativematerial. Power, from any suitable source, such as the 110 volt A.C.line 36 conventionally found in most homes, is applied to the electrodeterminals 38 and 40 through lines '42. When water in the containeroverflows into cup 26 an electrically conductive path is establishedbetween the electrodes. flow vaporizes the water within the containerultimately producing a substantial pressure head which acts to seat theball check valves in both the water feed line 14 and the air vent line16. This action closes both the mentioned conduits providing an airtight system from which water can only escape through discharge line 28,the opening of which is below the water level. Water which is retainedin the cup maintains the boiling action until all of the water in thecontainer, except that in the cup 26, is expelled from the apparatus.Operation terminates when water within the cup is vaporized. To preventvapor, which condenses within the container 18, from entering the cup,the cup rim is chamfered and the mouth of the cup narrowed in the mannershown in FIGURE 1. When boiling stops the pressure within the systemreturns to atmospheric and the check valves open. siphon is proportionedso that on closure of valve 22 there remains an operating head Ah, toinsure siphonic action on reopening of the feed valve, assuming, thatmouth 44 of the feed siphon remains submerged. The cycle is repeateduntil there is insufficient driving head to maintain siphonic action.

The provision of means such, for example, as the siphonic feed and valvemeans 14, 22, acting in coopation with the cup 26, is an importantfeature of the invention and insures complete and substantiallyinstantaneous immersion of operative portion-s of the electrode elements20 by the infiowing water. This system virtually eliminates highfrequency cycling of the electrode system, which action, is bothdetrimental to electrode life and wasteful of power Without beingproductive of any substantial pumping effect.

A mechanism designed to pump 3 pints of liquid per hour against an 8'foot head may comprise a 3" diameter container made of boro-silicateglass having a wall thickness of approximately /8 of an inch and avolumetric capacity of about one-half pint. The container is closed by aconventional screw-on metal lid 48 adapted to place the upper edge ofthe glass container into pressure-sealing relation with a gasket 49carried by the lid, made, of neoprene, rubber or other suitablematerial. The lid is hermetically traversed by three metal tubes 50, 51and 52 in the manner shown in FIGURE 1, the tubes being made of O.D.copper having a The heat generated by the resultant current The invertedU-tube 14 which forms the feed bore'and forming, respectively, theterminal legs of the feed line 14, air-vent line 16 and the dischargeline 28. Also carried by the lid are a pair of rectangular stainlesssteel electrodes wide and spaced approximately /s" apart. The electrodeterminals 38 and 46 extend through the lid and are hermetically sealedthereto and electrically insulated from each other and I r '4 the lid byrubber grommets 53 which are radially expanded into pressure seatingengagement with the cap on tightening of nut and bolt means 54. Theelectrodes as previously mentioned are connected to an appropriate V.AC. source through terminals 38 and 44). The flexible couplings 56 and58 interconnecting the container tubing with that carried by thecondensate pan are made of 1.1). plastic sleeving, e.g. Tygon. The part60 of the discharge line 4d extending outside th container Thisconstructed of similar material. To insure an air tight seal the coppertubing is hermetically sealed to the metal cap. One means of achievingsuch a seal is by use of glass beading 62 in the manner shown inenlarged section in FIGURE 2. A method for producing such a seal is thattaught in copending application Serial No. 760,454 filed September 11,1958, now Patent No. 3,069,876 and assigned to the assignee of thepresent invention.

The plastic cup or vessel 26 is of electrically insulative material andprovides a 1'-' diameter A" deep well into which terminal portions ofthe electrodes 20 extend. Both the'inle't and discharge tubes 50 and 52extend into the container to a depth below the level of the top 64 ofcup 26. I V

The pump mechanism described is capable of developing an operationalhead of 12 feet with an internally generated pressure of something lessthan 6 p.s.i.g. This duces to a point at which an equilibrium conditionexists in which the steam generated from the recondensing vapor is justsufiicient to maintain a static head within the discharge line 28. Underthis condition of operation the valves are maintained in a closedposition due to internal pressure. This action prevents the inflow ofwater and pumping action ceases with the unit energized. The use of acup avoids this stalled condition by isolating the electrodes from theWater vapor condensing within the system and permits operation only solong as there is water in the cup 26. Once the water within the cup isevaporated the system automatically shuts otf readying itself for thenext cycle of operation. After the cup 28 boils dry, and the pump coolsequalizing the container and ambient atmospheric pressuresassuming thecondensate pan has been emptied-water remaining in the feed siphon anddischarge line will drain into container 18. To avoid reactivation ofthe pump by this returning condensate the cup is made a heightsuflicient to prevent water from reaching the cup top. Looked at anotherway, the system is designed to provide sutficient storage capacity belowthe level of the shut oifcup 28, to accommodate the volume of liquidretained within the siphon and discharge lines on completion of anoperational cycle.

The arrangement shown will operate on a partial fill, a condition whichconceivably can exist on the final emptying of the condensate pan. Aslong as there is sufficient water to enter the shut-off cup 26, the pumpwill discharge a partial fill and automatically cycle ofi in the mannerdescribed.

Under normal operation, the feed rate of water entering the containerthrough siphon 14 is designed to be fast enough substantially to fillthe'container 18 before the pressure head developed by operation of theelectrode system closes the inlet check valve 22. This permits optimumuse of the pump and reduces its overall power requirements.

To further improve the systems operating efiiciency a heat insulativejacket 64 may be used as shown in FIG- URE 1. By reducing heat losses, apumping rate of about 3 pints of condensate per hour, based on anoperational r head of 8 feet, can be maintained with an average powerconsumption of approximately 110 watts.

One area of construction which is of particular importance to properunit operation is the air-vent valve system 22. A valving arrangement,in addition to that shown in FIGURE 1, found to be satisfactory is thatshown in enlarged section in FIGURE 2. The valve comprises a pair of/56" OD. copper tubes 66 and 68 the confronting ends 70 and 72 of whichare terminated in short lengths of A I.D. copper tubing 74 and 76interconnected by a ID. plastic sleeve 78 stretched over the copperterminations to provide an air-tight interconnection of the tube ends.Housed within this valve cage is a ball 79, equivalent to the ball 34shown in FIGURE 1. A molded valve seat 80, also made of plastic, orother suitable material, is seated against the shoulder provided by theend 70 of tube 66 and press fit within the cavity defined by thatshoulder and the internal bore of termination 74. The valve seat isprovided with a internal bore 82 and a hemispherically shaped pocket 84for receipt of ball 79 in the manner shown in phantom in FIG- URE 2,this being its seated or operating position. The ball 79 may be made ofglass, plastic, rubber, or any other suitable material. A desirablerequirement in the illustrated embodiment is that the ball besubstantially spherical in configuration. The valve seat alternativelymay be made simply of an annulus of rubber without the provision of apocket for receipt of the ball provided the rubber has a durometer valuemaking it sufiiciently yieldable to conform to the surface configurationof the ball when the ball is urged against the valve seat by the normaloperating pressure of the system. A ball weighing approximately 105milligrams having a diameter of about .173 inch provided satisfactoryoperation when used in valving of the type described and illustrated inFIGURE 2. To prevent blockage of opening 86 by ball 79 when in itsunseated position the tube end is chamfered. An

alternative arrangement permitting one-way fiow is seen in FIGURE 1 andconsists of using an obliquely disposed flap 88 which acts partially toobturate the entrance to the tube preventing blockage.

The mechanism described is capable of pumping to a drain located fromeight to twelve feet above the level of the dehumidifier, is noiselessand automatic in operation and is of relatively inexpensiveconstruction. One use of the invention is as a kit or accessory for usewith currently installed condensate generating air conditioningequipment.

While preferred forms of the present invention have been depicted anddescribed, it will be understood by those skilled in the art that theinvention is susceptible of changes and modifications without departingfrom the essential concepts thereof, and that such changes andmodifications are contemplated as come within the terms of the appendedclaims.

I claim:

1. A liquid pumping system comprising: liquid-storage means; a containerfor the receipt of liquid from said liquid-storage means; electrodemeans extending into said container; liquid feed means interconnectingsaid storage means and container in fluid-flow communication includ inga conduit arranged to provide for flow of liquid from said storage meansto said container when the liquid in said storage means reaches apredetermined upper level and to maintain liquid flow to said containerby siphonic action until the liquid in said storage means reaches apredetermined lower level; valve means associated with said conduitconstructed to permit flow of liquid to said container and to preventflow of liquid in the reverse direction; means for venting air from saidcontainer including valve means constructed and arranged to permit theescape of air displaced by the incoming liquid, to close when theair-flow rate exceeds that produced by water inflow, and to open whenthe pressure within said container becomes equal to or less than theambient atmospheric pressure; liquid-venting means including an openconduit extending substantially to the bottom of said container; afloatable, electrically insulative open-ended vessel disposed in saidcontainer into which terminal portions of said electrode means extendcaptively to permit flotation of said vessel, by incoming liquid, to apredetermined elevational level, such that liquid overflowing into thevessel when at said level results in rapid submergence thereof producingcomplete and substantially instantaneous immersion of said electrodemeans by overflowing liquid; and means impressing a voltage across saidelectrode means to provide, on establishment of an electricallyconductive path to said electrode means by said overflowing liquid, heatsulficient to effect gradual vaporization of said liquid to develop apressure within said container sufficient to eflect closure of saidvalve means and discharge of liquid through said liquid venting means.

2. Liquid pump mechanism, comprising: a container for liquid to bepumped; a pair of mutually insulated, spaced electrodes disposed withinsaid container; liquid inlet means including a conduit valved to permitundirectional flow of liquid into said container; air-venting meansassociated with said container valved to permit the escape of air fromsaid container displaced by incoming liquid and to close when the airflow rate exceeds that produced by liquid inflow and to open onequalization of the containers internal pressure with that of theambient atmosphere; an electrically insulative floatable cup disposedwithin and at the bottom of said container and into which saidelectrodes extend, said cup being constructed and arranged to insulatethe electrodes one from the other until liquid within said containeroverflows into said cup, and said electrodes extending into said cup toa depth permitting captive flotation thereof to a level which onsubmersion by overflowing liquid produces complete and substantiallyinstantaneous immersion of said electrodes by overflowing liquid; and anopen conduit communicating with said container one end of which extendsinto said container to a depth below the level of the top of said cup;and means impressing a voltage across said electrodes of a value togenerate, on immersion of said electrodes by overflow of liquid intosaid cup, heat sufficient to effect gradual vaporization of liquidwithin said container to develop an internal pressure effecting closureof the mentioned valving and discharge of liquid through said openconduit.

3. A water pump comprising: a container for receipt of water to bepumped; a pair of mutually insulated, spaced electrodes disposed withinsaid container; means for feeding water to said container, includingvalving constructed to permit unidirectional flow of water into saidcontainer but to prevent flow of water in the reverse direction; meansfor venting air from said container including valving constructed topermit the escape of air from said container displaced by the inflow ofwater and to close when the flow rate exceeds that produced by waterinflow, and to open on the pressure within said container becomingsubstantially equal to that of the ambient atmosphere; 9.water-discharge conduit extending substantially to the bottom of saidcontainer; a fioatable, cup-like, electrically insulative memberdisposed within said container into which terminal portions of saidelectrodes extend to a depth permitting captive flotation of saidmember, by incoming water, to a predetermined level, and said memberbeing constructed to prevent the establishment of an electricallyconductive path between said electrodes by water entering said containeruntil the water accumulating within said container reaches a levelsuflicient to overflow into said cup-like member when in its fullybuoyed position and rapidly to submerge said member by overflowing waterwith resultant complete and substantially instantaneous immersion ofsaid electrodes; and means for electrically energizing said electrodesto provide, on establishment of an electrically conductive path betweensaid electrodes by water overflowing into said cup, heat suflicient toeffect vaporization of such water to develop, by vaporization of same, apressure within said container 7 8 sufficient to effect closure of saidvalving and discharge container into said vessel when in its fullybuoyed posiof Water through said discharge means. tion.

4. In pumping mechanism of the type described, the References Cited bythe Examiner combination comprising: a container for receipt of liquidUNITED STATES PATENTS to be pumped, a floatable open-ended vesseldisposed 5 Within said container; means delimiting the elevational1226758 5/17 DuftX 137 132 level to which said vessel is buoyed byliquid entering said 2976879 3/61 De Lisle et a1 137*132 container andproviding for operation of said pumping 21065 ,712 11/62 Buchanan et 103255 3,094,134 6/63 Curne 13713Z mechanism, including electrode meanspositioned within I said container at a location insuring substantiallyinstanta- 10 neous immersion of operative portions thereof on sub-LAURENCE EFNER P Examiner mergence of said vessel by liquid overflowingfrom said ROBERT M. WALKER, Examiner.

1. A LIQUID PUMPING SYSTEM COMPRISING: LIQUID-STORAGE MEANS; A CONTAINERFOR THE RECEIPT OF LIQUID FROM SAID LIQUID-STORAGE MEANS; ELECTRODEMEANS EXTENDING INTO SAID CONTAINER; LIQUID FEED MEANS INTERCONNECTINGSAID STORAGE MEANS AND CONTAINER IN FLUID-FLOW COMMUNICATION INCLUDING ACONDUIT ARRANGED TO PROVIDE FOR FLOW FO LIQUID FROM SAID STORAGE MEANSTO SAID CONTAINER WHEN THE LIQUID IN SAID STORAGE MEANS REACHES APREDETERMINED UPPER LEVEL AND TO MAINTAIN LIQUID FLOW TO SAID CONTAINERBY SIPHONIC ACTION UNTIL THE LIQUID IN SAID STORAGE MEANS REACHES APREDETERMINED LOWER LEVEL; VALVE MEANS ASSOCIATED WITH SAID CONDUITCONSTRUCTED TO PERMIT FLOW OF LIQUID TO SAID CONTAINER AND TO PREVENTFLOW OF LIQUID IN THE REVERSE DIRECTION; MEANS FOR VENTING AIR FROM SAIDCONTAINER INCLUDING VALVE MEANS CONSTRUCTED AND ARRANGED TO PERMIT THEESCAPE OF AIR DISPLACED BY THE INCOMING LIQUID, TO CLOSE WHEN THEAIR-FLOW RATE EXCEEDS THAT PRODUCED BY WATER INFLOW, AND TO OPEN WHENTHE PRESSURE WITHIN SAID CONTAINER BECOMES EQUAL TO OR LESS THAN THEAMBIENT ATMOSPHERIC PRESSURE; LIQUID-VENTING MEANS INCLUDING AN OPENCONDUIT EXTENDING SUBSTANTIALLY TO THE BOTTOM OF SAID CONTAINER; AFLOATABLE, ELECTRICALLY INSULATIVE OPEN-ENDED VESSEL DISPOSED IN SAIDCONTAINER INTO WHICH TERMINAL PORTIONS OF SAID ELECTRODE MEANS EXTENDCAPTIVELY TO PERMIT